Means for the rotational reversal of diesel and the like engines



p 1935- E. P. PAXMAN 2,013,580

MEANS FOR THE ROTATIONAL REVERSAL OF DIESEL AND THE LIKE ENGINES Filed Aug. 25, 1954 3 Sheets-Sheet l INVENTOR EDWARD P. PAXMAN ATTORNEYS Sept; 3, 1935. E; P. PAXMAN 2,013,580

MEANS FOR THE ROTATIONAL REVERSAL OF DIESEL AND THE LIKE ENGINES 3 Sheet s-Sheet 2 Filed Aug. 25, 1934 HIE] la",

INvEN'rofi EDWARD P. PAXIIAN ATTORNEYS Sept. 3, 1935. PAXMAN 2,013,580

MEANS FOR THE ROTATIONAL REVERSAL OF DIESEL AND THE LIKE ENGINES Filed Aug. 25, 1954 s Sheets-Sheet 3 EDWARD P. PAXMAN Patented Sept. 3, 1935 UNITED STATES MEANS FOR THE ROTATIONAL REVERSAL OF DIESEL AND THE LIKE ENGINES Edward Phillip Paxman, Colchester, England Application August 25, 1934, Serial No. 741,486 In Great Britain August 24, 1933 11 Claims.

This invention relates to means for the rotational reversal of Diesel and the like engines and has for its object to provide an improved construction and arrangement whereby reversion of rotation is simply effected without modification or duplication of the valve gear in either two or four stroke cycle engines, and in which a single control device can operate the change over as well as regulate the speed.

In some forms of Diesel engines, the reversal of direction of rotation is accomplished by having alternative cam shafts or again by having a single cam shaft whose angular position is moved so as to provide a correct position for the air and exhaust valve and jet operation. These latter devices, however, involve considerable additional expense in construction by reason of the linkage necessary for the change over gear and the controls of the engine for this operation. For all marine purposes, however, it is essential that the engine should reverse and it is, moreover, preferable that the engine itself be reversed rather than that reversal of the propeller shaft takes place through gear intermediate of the engine and the propeller.

According to the invention, means are provided for reversing a Diesel or like engine wherein a manual control device is arranged to operate the switch gear of an electric starter or starters to turn the engine in the required direction whilst simultaneously controlling and timing the oil fuel supply.

In carrying the invention into effect according to the preferred form, a manually operated control wheel is connected by linkage with a transverse shaft carrying means for controlling the fuel supply and also operates switches through the medium of gearing and which switches control two electric starting devices of known type adapted to engage a toothed wheel formed integral with or disposed adjacent to the fly wheel of the engine.

Reference will now be made to the accompanying drawings which illustrate by way of example a construction according to the invention and in which:-

Figure 1 is an elevation partly in section;

Figure 2 is an end elevation corresponding to Fig. 1;

Figure 3 is a detail, partly longitudinal sectional view showing the drive to the fuel pump;

Figure 4 is a detail view, partly in cross section, showing the face of one of the clutch members shown in Fig. 3;

Figure 5 is a fragmentary view partly in side elevation and partly in section, illustrating a modified form using compressed air starting motors;

Figure 6 is a fragmentary end elevation of the form of Figure 5;

Figm'e 7 is a. fragmentary View in side eleva-. tion suggesting a remote control for the engine;

Figure 8 is a fragmentary side elevation of a form using a, servo motor, and

Figure 9 is a detail sectional view illustrating the drive between said servo motor and control means.

In the construction illustrated a manually operated control wheel I mounted on a standard 2 at one side of the engine housing 3 is connected by linkage with a transverse counter shaft l disposed below a fuel pump 5. The engine is provided with two electric starting devices 6 of known type either of which is adapted to engage a toothed wheel 1 formed integral with or disposed adjacent to the fly wheel of the engine.

The control wheel I is mounted on a spindle 8 rotatably mounted in the standard 2, the said spindle having keyed thereon wheel or disc 9 which operates in conjunction with a fixed pointer Ill adapted to co-operate with markings on the wheel 9 to adjust the latter correctly to posi-. tions marked ahea astern, stop, etc., shown in Fig. 1.

The spindle 8 also carries within the standard 2 a sprocket wheel H, chain l2 passing around this sprocket wheel and around a second sprocket wheel l3 disposed on a control shaft M in the base l5 of the standard 2. Mounted on the shaft I l are two pawls l6 adapted when moved to their lowest positions to bear upon arms ll pivoted to the sides of the casing l5 and bearing in turn upon switching devices l8 which control the operation of the electric starters 6.

The shaft M has mounted thereon an eccentric whose rod I9 is connected at its outer end to an arm 2|! mounted on a transverse counter shaft 2| on which is also mounted an arm 22 whose upper forked end engages between the flanges of a, sleeve 23 slidably mounted on the engine camshaft 24 (see Fig. 3), a key 25 being interposed between the sleeve and shaft to prevent relative rotational movement between them. The key 25 also serves to retain in position on the end of the shaft a driving member 25 of a dog coupling, the driven member 2i of which is fixed on the adjacent end ofthe driving shaft 28 of the fuel pump 5. The two dogs 26 and 21 are so arranged that they can drive on alternate faces 29 and 30 (for ahead or astern) the positions of these driving faces being so arranged (see Fig. 4) as to give the requisite timing to the fuel pump.

To prevent backlash, means are provided for locking the dogs together in either driving position, these means comprising in the construction illustrated studs or pins 3! fixed in the flange of sleeve 23 and adapted to pass through the driving dog 26 and engage in either of two pairs of sockets 32 and 33 formed in the driven dog 21.

The shaft l4 also carries an arm 34 connected by means of a link 35 with an arm 36 on the transverse shaft 4 capable of being partially rotated and. having thereon an'arm 38 whose upper end engages around the fuel pump control spindle 39 with which it has a resilient connection through a spring 40 bearing at its outer end on a disc 4| fixed at the end of the said spindle. The opposite end of the control spindle 39 is also engaged by an arm 42 operated by the engine governor, this arm also bearing on the end of the spindle through the medium of a spring 43. The transverse shaft 4 also carries an arm 44 adapted, when the control wheel I is moved in either direction from the stop position, to engage a member 45 forming part of the governor mechanism. The arm 42 is carried by a transverse shaft 46 extending between the governor mechanism and the fuel pump.

When the parts are in the stop position as shown, a plunger 4! movable in. a cylinder 48 and operated by oil pressure in the engine, engages a notch in a rotary disc 49 mounted on the outer end of the shaft l4 so as to be moved synchronously with the control wheel I to lock this wheel against further movement until the engine stops and thus prevent a false move being made. When the engine has stopped, the oil pressure is relaxed and the plunger 41 drops by gravity to release the control wheel for further movement.

The operation of the engine constructed as above described is as folloWs:

In the stop position illustrated the fuel supply is completely cut off, the governor is in the 3 position for slowest running, neither starter 6 is engaged and the fuel pump driving dogs 26 and 21 are out of driving contact with the pins 3! withdrawn.

When the wheel I and disc 9 are moved to the start position, either ahead or astern, the shaft I4 is partially rotated, and one of the pawls I6 is moved against an arm ll to close a switch l8 to operate one of the starters 6. Through the said partial rotation of wheels I and 9, both transverse shafts 4 and 2! are rocked. These operations cause a limited amount of fuel to be admitted through the fuel pump as the dogs 26 and 21 have an initial relative movement and then become engaged as the engine rotates.

As the control wheel I is moved to the next po sition (slow speed) the starter is cut out, the pawl I6 having reached a position wherein it no longer depresses the arm IT. The fuel supply is increased as the transverse shaft 4 is rocked further in a clockwise direction (Fig. 1) allowing spring 43 to move the fuel pump control spindle 39 as arm 38 moves towards the right. The pins 3| lock the dogs 26 and 21 together and continued motion of the control wheel I up to the full speed position increases the load on the governor by the action of arm 44 moving in a clockwise direction.

As the control wheel I is returned towards the stop position, the transverse shaft 4 is rocked in an anti-clockwise direction and the transverse shaft 2| is rocked in a clockwise direction so that the governor load and fuel supply are diminished until the latter is cut off entirely and meanwhile the pins 3! are withdrawn and the dogs 26 and 21 disengaged. The pawls l6 are arranged so that they can yield in one direction so that during the return movement to the stop position operation of either starter 6 is prevented.

When the stop position is reached the plunger 41 prevents further movement of the wheel I so that movement of the gear from ahead to astern position or vice versa is prevented whilst the engine is running. When the direction of rotation; is reversed, the alternate faces of the dogs 26 and 21 engage, this entailing a slight time lag to obtain correct fuel injection timing for the reversed direction of movement.

It is to be understood that the invention is not limited to the employment of two electric starters as one reversible starter may be employed operated by appropriate switch gear under control of the hand wheel. Alternately compressed air motors or other starting devices may be employed, the control wheel being linked with the fuel valve and governor as already described.

Such compressed air starters are shown at 50 in Figs. 5 and 6 as operatively connected with control valve mechanisms 5| adapted to be opened one at a time and in accordance with the direction of rotation through engagement of pivoted arms l1 therewith, in turn engageable by pawls l6 corresponding to those at l6; such pawls It being carried by a chain l2, operable in the same manner and for the same purpose as chain l2.

The control may be arranged remote from the engine as suggested in Fig. '7, where a box IE, rigid with a fixed part of the engine, is built about the control shaft l4. The single control mechanism C corresponding to the parts which operate the chain, here shown at I2", is mounted on a different support 60 from the engine. Sheathing 6i encloses said chain l2" between the box l5 and control C.

The control may also be operated by a servo motor according to Figs. 8 and 9 where such servo motor is designated 1!! and which, through the medium of worm or equivalent gearing H, is adapted to drive a control shaft 8' functioning like that at 8. It may in some cases also be desirable to introduce a clutch of known type which is interposed in the main drive shaft between the engine and the load and is arranged to be disengaged by a servo motor or other means actuated from the control wheel when the said wheel is in positions near to slow on each side of the stop position, and thus automatically reduce the load on starting, and enable the engine to be kept running slow in either direction with clutch disengaged.

I claim:

1. Means for reversing a Diesel or like engine having a fuel pump and starting mechanism provided with electric switches adapted to be independently closed to cause operation of the engine in opposite directions, a control wheel rotatable in opposite directions from neutral or stop position, a control shaft, means to turn said shaft in either direction from the control wheel, a spring-controlled governor for said fuel pump, elements carried by said shaft to operate either one of said switches depending on the direction of movement of the control wheel from the stop position, first and second counter shafts, means to operate the two counter shafts from the control shaft, mechanism to drive the fuel pump consisting of a loose coupling connection adapted to be adjusted to either one of two positions, means for locking said coupling operable from the first counter shaft after the control wheel has been moved beyond the starting position, and mechanism operable by the second counter shaft after the control wheel has been moved beyond the starting position to control the amount of delivery from the fuel pump and the pressure on the governor spring.

2. Means for reversing a Diesel or like engine according to claim 1 wherein said last named mechanism has an axially slidable element directly controlling the amount of delivery of the fuel pump and an operating arm connected to said slidable element and second counter shaft and an arm responsive to movements of the governor connected to said slidable element and urging opening thereof.

3. Means for reversing a Diesel or like engine according to claim 1 wherein the second mentioned mechanism has an arm to increase the pressure on the governor spring as the control wheel is moved towards either full speed position.

4. Means for reversing a Diesel or like engine according to claim 1 having a disk on the control shaft provided with a notch, oil circulating means maintaining oil under pressure only while the engine is turning over, and a plunger operable by this pressure engaging said notch to lock the control wheel in stop position, and means urging said plunger to retracted position.

5. Means for reversing a Diesel or like engine according to claim 1 having a pair of arms, one associated with each switch, the aforesaid elements on the control shaft being pawls either of which as the shaft rotates in opposite directions contacts with and depresses one of said arms to actuate the corresponding switch.

6. Means for reversing a Diesel or like engine comprising a control wheel, a control shaft, means to operate said control shaft in opposite directions from neutral or stop position by movement of said wheel, a pair of starting devices, a pair of pawls carried by said shaft each controlling the operation of one of said starting devices, two counter shafts, means to rock said counter shafts through rotary movement of said control shaft, a fuel pump having a governor provided with a spring, loose coupling means for timing the pump in accordance with the direction of rotation, means operable by one of said counter shafts to lock said coupling, means for controlling the amount of fuel pump delivery and for varying the pressure of the governor spring operable by the other counter shaft, and means for locking the control shaft when in the stop position while the engine is in motion.

'7. A control mechanism for a reversible engine of the fuel-injection type, comprising a control means movable in either direction from a neutral or stop position, a control shaft connected to and operated thereby to be rotated in either direction, starter control elements operated by the control shaft to initiate engine rotation in either direction depending on the direction of rotation of the control shaft upon initial movement of the control means from its stop position, a fuel pump having a fuel quantity control and a springactuated speed-responsive governor connected thereto, another control element connected to the control shaft and operating the fuel quantity control upon further movement of the control means and within a portion of the range of this movement operating to vary the tension of the governor spring, a loose coupling connection on the fuel pump drive shaft to effect a proper timing of the fuel injection during rotation of the engine in either direction of engine rotation, means for locking said loose coupling to prevent accidental displacement of its parts during normal running, and still another control element connected to the control shaft operating the looking means to lock the connection when the control means are moved beyond the starting position- 8. A control mechanism according to claim 7 having means operated by the engine for circulating oil under pressure, means responsive to this pressure for locking the control means when moved into the stop position before the engine has come to rest, and means for releasing this locking means Whenever the engine is at rest.

9. In apparatus of the class described for an engine having a fuel pump, means operable to rotate in either direction from neutral or stop position to start the engine in the corresponding direction, including control elements, one to initiate rotation of the engine in each direction, a loose coupling connection on the fuel pump drive shaft to effect a proper timing of the fuel injection during rotation of the engine in either direction, a rock-shaft having means to actuate each control element independently through movement of said rock-shaft in either direction, means operable through the rock-shaft to lock the coupling, and means operable through the rock-shaft to control the amount of fuel delivered by the pump, said third and fourth mentioned means being operable in succession.

10. In a means for reversing a Diesel or like engine having a fuel pump, two starting devices having control elements and a cam shaft, the combination of a control Wheel rotatable in either direction from neutral or stop position, a control shaft having means to individually operate said elements, means to turn the control shaft in either direction from the control wheel, and clutch means connected with the control shaft operable after said control wheel has been moved beyond the starting position in either direction for controlling the quantity of fuel supply, said clutch means comprising a part on the fuel pump and a part loosely engaged therewith carried by the engine cam shaft, said parts being drivingly engageable in either direction of rotation, the said loose interengagement of said parts when changing over from one direction to the other providing a slight time lag to effect correct fuel injection timing, said clutch means also including a sleeve on said engine cam shaft, pins on said sleeve, and means connected to the control shaft to engage said pins with holes in both of said parts to lock them together when the control device is moved beyond the start position in either direction.

11. In a means for reversing a Diesel or like engine having a fuel pump and two starting devices having control elements, the combination of a control wheel rotatable in either direction from neutral or stop position, a control shaft having means to individually operate said elements, means to turn the control shaft in either direction from the control wheel, means connected with the control shaft operable after said control wheel has been moved beyond the starting position in either direction for controlling the quantity of fuel supply, oil circulating means maintaining oil under pressure only while the engine is turning over, and means operable by this pressure to lock the control wheel in the stop position whenever it is moved into said position while the engine is in motion.

EDWARD PHILLIP PAXMAN. 

